Academic Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, Sheffield, United Kingdom. shcoleman1@sheffield.ac.uk. Academic Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, Sheffield, United Kingdom. anupam.rej@nhs.net. Academic Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, Sheffield, United Kingdom. emrbaggus1@sheffield.ac.uk. Academic Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, Sheffield, United Kingdom. michelle.lau3@nhs.net. Academic Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, Sheffield, United Kingdom. ljsmarks1@sheffield.ac.uk. Academic Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, Sheffield, United Kingdom. m.hadjivassiliou@nhs.net. Academic Unit of Pathology, Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom. s.s.cross@sheffield.ac.uk. Celiac Center and Division of Gastroenterology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA. dleffler0603@gmail.com. Center for Prevention and Diagnosis of Celiac Disease, Division of Gastroenterology and Endoscopy, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy. lucelli@yahoo.com. Academic Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals, Sheffield, United Kingdom. david.sanders1@nhs.net.